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   to you under the Apache License, Version 2.0 (the
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.. include:: ../common.defs

.. _whats_new:

What's New in ATS v10.x
=======================

This version of |ATS| includes over <x> commits, from <y> pull requests. A
total of <z> contributors have participated in this development cycle.

.. toctree::
   :maxdepth: 1

New Features
------------

* JSON-RPC based interface for administrative API

   |TS| now exposes a JSON-RPC node to interact with external tools. Check :ref:`developer-guide-jsonrpc` for more details.

* traffic_ctl has a new command ``monitor`` to show a continuously updating list of metrics

* :file:`ip_allow.yaml` and :file:`remap.config` now support named IP ranges via IP
  Categories. See the ``ip_categories`` key definition in :file:`ip_allow.yaml`
  for information about their use and definitions.

* :file:`sni.yaml` ``fqdn:tunnel_route``, beside the already supported match group
  number, configuration now also supports the destination port using a variable specification
  either for the incoming connection port or the port that was specified by the
  incoming Proxy Protocol payload. Check :file:`sni.yaml` for more information.

* The records.yaml entry :ts:cv:`proxy.config.system_clock` was added to control the underlying
  system clock that ATS uses for internal timing

New or modified Configurations
------------------------------

ip_allow.yaml and remap.config ACL actions
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

There are two new sets of actions for HTTP request method filtering introduced in |TS| 10.x:

- Both :file:`ip_allow.yaml` and :file:`remap.config` now support the ``set_allow`` and ``set_deny`` actions. These
  actions both behave like ``allow`` and ``deny`` did for :file:`ip_allow.yaml` pre |TS| 10.x.
- In addition, :file:`remap.config` now supports ``add_allow`` and ``add_deny`` actions. These behave like ``allow``
  and ``deny`` actions did for :file:`remap.config` ACLs pre |TS| 10.x.

The details about the motivation and behavior of these actions are documented in :ref:`acl-filters`.

Logging and Metrics
-------------------

Plugins
-------

* authproxy - ``--forward-header-prefix`` parameter has been added
* prefetch - Cmcd-Request header support has been added
* xdebug - ``--enable`` option to selectively enable features has been added
* system_stats - Stats about memory have been added
* slice plugin - This plugin was promoted to stable.

JSON-RPC
^^^^^^^^

   Remote clients, like :ref:`traffic_ctl_jsonrpc` have now bi-directional access to the plugin space. For more details check :ref:`jsonrpc_development`.

Replaced autotools build system with cmake
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

See :ref:`admin-installing` for more information

Switch to C++20
^^^^^^^^^^^^^^^

Plugins are now required to be compiled as C++ code, rather than straight C.
The API is tested with C++20, so code compatible with this version is preferred.
``TSDebug`` and related functions are removed.  Debug tracing should now be done
using cpp:func:`Dbg` and related functions, as in |TS| core code.

C++ Plugin API Deprecated
^^^^^^^^^^^^^^^^^^^^^^^^^

It is deprecated in this release.  It will be deleted in ATS 11.

Symbols With INKUDP Prefix
^^^^^^^^^^^^^^^^^^^^^^^^^^

In the plugin API, all types and functions starting with the prefix INKUDP are removed.

New plugin hook for request sink transformation
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

A new hook, ``TS_HTTP_REQUEST_CLIENT_HOOK``, has been added. This provides the analoguas functionality of
``TS_HTTP_RESPONSE_CLIENT_HOOK``, for request bodies.

HTTP/2
^^^^^^

* Support for HTTP/2 on origin server connections has been added. This is disabled by default. For more details check :ts:cv:`proxy.config.ssl.client.alpn_protocols`
* Support for CONNECT method has been added.
* Window size control has been improved. For more details check :ts:cv:`proxy.config.http2.flow_control.policy_in`

HTTP UI Removed
^^^^^^^^^^^^^^^

The stats and cache inspector pages were unmaintained and removed in this
release.


